Testing Bell's inequality with cosmic photons: closing the setting-independence loophole.

Bell-inequality violation with entangled photons, free of the coincidence-time loophole

Violation of local realism with freedom of choice.

Bell's theorem shows that local realistic theories place strong restrictions on observable correlations between different systems, giving rise to Bell's inequality which can be violated in experiments using entangled quantum states. Bell's theorem is based on the assumptions of realism, locality, and the freedom to choose between measurement settings. In experimental tests, "loopholes" arise wh...

Cosmic Bell Test: Measurement Settings from Milky Way Stars.

Bell's theorem states that some predictions of quantum mechanics cannot be reproduced by a local-realist theory. That conflict is expressed by Bell's inequality, which is usually derived under the assumption that there are no statistical correlations between the choices of measurement settings and anything else that can causally affect the measurement outcomes. In previous experiments, this "fr...

ua nt - p h / 04 06 04 2 v 3 2 5 Ju l 2 00 4 Complete Correlation , Detection loophole and Bell ’ s Theorem

Two new formulations of Bell’s theorem are given here. First, we consider a definite set of two entangled photons with only two polarization directions, for which Bell’s locality assumption is violated for the case of perfect correlation. Then, using a different approach, we prove an efficient Bell-type inequality which is violated by some quantum mechanical predictions, independent of the effi...

ua nt - p h / 04 06 04 2 v 2 1 5 Ju n 20 04 Compelet Correlation , Detection loophole and Bell ’ s Theorem

Two new formulations of Bell’s theorem are given here. First, we consider a definite set of two entangled photons with only two polarization directions, for which Bell’s locality assumption is violated for the case of perfect correlation. Then, using a different approach, we prove an efficient Bell-type inequality which is violated by some quantum mechanical predictions, independent of the effi...